Can you teach me not to be angry? Relations between temperament and the emotion regulation strategy distraction in 2-year-olds

Little is known about toddlers’ acquisition of specific emotion regulation (ER) strategies, and how early ER is shaped by temperament. This study investigated if 24-month-old German toddlers, predominantly from families with high levels of parental education (N = 96, n = 49 male), learned the ER strategy distraction through observational learning, and its interaction with temperament. Increased use of distraction correlated with reduced negative affect. Use of distraction increased through observational learning. Highly active toddlers tended to use active playing activities to distract themselves in a frustrating situation, whereas toddlers with a less active temperament used calmer activities. Toddlers’ learning to apply distraction through observational learning was independent of a match between their own temperament and the model's actions.     

Hematocrit and flow rate regulate the adhesion of platelets to von Willebrand factor

Primary hemostasis and blood clotting is known to be influenced by the red blood cell volume fraction (hematocrit) in blood. Depressed or elevated levels of red blood cells can lead to vascular perfusion problems ranging from bleeding to thrombus formation. The early stage of hemostasis and thus blood clotting in all vessel sections from the arterial to the venous system involves the adhesion of platelets to von Willebrand factor. Here we present experimental and theoretical results showing that the adhesion probability of platelets to von Willebrand factor is strongly and nonlinearly dependent on hematocrit and flow rate. Interestingly, the actual binding forces are not markedly different, which suggest that the origin of such behavior is in the distribution of platelets. Using hydrodynamic simulations of a simple model, we explicitly show that the higher the hematocrit and the flow rate, the larger the amount of platelets residing close to the wall. Our simulation results, which are in excellent agreement with the experimental observations, explain why such phenomena occur. We believe that the nonhomogeneous red blood cell distribution as well as the shear dependent hydrodynamic interaction is key for the accumulation of platelets on the vessel wall. The work we present here is an important step forward from our earlier work on single molecules and extends into the collective cellular behavior of whole blood. It sheds new light on the correlation between hematocrit and the initial steps in hemostasis and thrombosis, and outlines advances for the treatment of vascular diseases associated with high levels of red blood cells. These results are not only highly relevant for the field of hemostasis and the physics of blood clotting but are also of powerful impact in applied science most obviously in drug delivery and colloidal science.     

Circulating but not immobilized N-deglycosylated von Willebrand factor increases platelet adhesion under flow conditions

The role of von Willebrand factor (VWF) as a shear stress activated platelet adhesive has been related to a coiled-elongated shape conformation. The forces dominating this transition have been suggested to be controlled by the proteins polymeric architecture. However, the fact that 20% of VWF molecular weight originates from glycan moieties has so far been neglected in these calculations. In this study, we present a systematic experimental investigation on the role of N-glycosylation for VWF mediated platelet adhesion under flow. A microfluidic flow chamber with a stenotic compartment that allows one to mimic various physiological flow conditions was designed for the efficient analysis of the adhesion spectrum. Surprisingly, we found an increase in platelet adhesion with elevated shear rate, both qualitatively and quantitatively fully conserved when N-deglycosylated VWF (N-deg-VWF) instead of VWF was immobilized in the microfluidic channel. This has been demonstrated consistently over four orders of magnitude in shear rate. In contrast, when N-deg-VWF was added to the supernatant, an increase in adhesion rate by a factor of two was detected compared to the addition of wild-type VWF. It appears that once immobilized, the role of glycans is at least modified if not—as found here for the case of adhesion—negated. These findings strengthen the physical impact of the circulating polymer on shear dependent platelet adhesion events. At present, there is no theoretical explanation for an increase in platelet adhesion to VWF in the absence of its N-glycans. However, our data indicate that the effective solubility of the protein and hence its shape or conformation may be altered by the degree of glycosylation and is therefore a good candidate for modifying the forces required to uncoil this biopolymer.     

Anorexia athletica in pre-professional ballet dancers

Abstract

Competitive sport has been under increasing discussion as a possible favourable factor in the development of eating disorders among children and adolescents. The aim of this study was to determine the frequency of sport-specific eating disorders, in line with the concept of anorexia athletica. This prospective field study included one experimental group and two control groups (disease and healthy). Fifty-two pre-professional ballet dancers aged 13–20 years were tested for clinical eating disorders, anorexia athletica criteria, eating disorder related psychopathology and self-concept, and were compared with 52 patients with anorexia nervosa and 44 non-athletic controls of the same age. The study was conducted using semi-structured interviews as well as self-report questionnaires. A clinical eating disorder diagnosis was made in 1.9% of the ballet dancers versus 0% of the high school students; anorexia athletica was diagnosed in 5.8% of the dancers versus 2.3% of the students. Ballet dancers scored lower than patients with anorexia nervosa with regard to eating disorder related psychopathology and higher than the patients with regard to self-concept. We conclude that more sensitive tools to differentiate between sport-specific (eating) patterns, anorexia athletica and clinically relevant eating disorders are needed, especially for aesthetic sports such as ballet. It remains an important goal to identify athletes with symptoms of anorexia athletica irrespective of their physique and/or sport.     

A Two-Generation Education Intervention and Children’s Attendance in Head Start

Two-generation human capital programs seek to promote the education of parents and children simultaneously. This study examines relations between family participation in CareerAdvance, which recruits parents of Head Start children into a workforce training program, and children’s Head Start attendance. The sample included 293 children (on average 4 years old) and their parents. After one semester, CareerAdvance children demonstrated higher rates of attendance and lower rates of absence and chronic absence (missing 10% or more of school days) than matched comparison children. These associations were similar across a range of high- and low-risk subgroups at baseline. These findings are discussed in terms of the implications of a family systems approach for improving children’s Head Start attendance.     

Human genetic variation: new challenges and opportunities for doping control

Sport celebrates differences in competitors that lead to the often razor-thin margins between victory and defeat. The source of this variation is the interaction between the environment in which the athletes develop and compete and their genetic make-up. However, a darker side of sports may also be genetically influenced: some anti-doping tests are affected by the athlete's genotype. Genetic variation is an issue that anti-doping authorities must address as more is learned about the interaction between genotype and the responses to prohibited practices. To differentiate between naturally occurring deviations in indirect blood and urine markers from those potentially caused by doping, the "biological-passport" program uses intra-individual variability rather than population values to establish an athlete's expected physiological range. The next step in "personalized" doping control may be the inclusion of genetic data, both for the purposes of documenting an athlete's responses to doping agents and doping-control assays as well facilitating athlete and sample identification. Such applications could benefit "clean" athletes but will come at the expense of risks to privacy. This article reviews the instances where genetics has intersected with doping control, and briefly discusses the potential role, and ethical implications, of genotyping in the struggle to eliminate illicit ergogenic practices.     

Early development of quantity to number-word linkage as a precursor of mathematical school achievement and mathematical difficulties: Findings from a four-year longitudinal study

This article reports results of a four-year longitudinal study that investigated the impact of specific and non-specific precursors on mathematical school achievement. Preschool quantity-number competencies (QNC) predicted mathematical achievement in primary school. Furthermore, basic arithmetic fact retrieval in Grade 1 had an impact on early mathematics school achievement. The influence of socioeconomic status and number naming speed, assessed in kindergarten, became especially important at the end of Grade 4. Particularly, a subgroup of mathematically low-achieving children in Grade 4 had already performed more poorly than normal children in tasks assessing preschool QNC, number naming speed, and basic arithmetic fact retrieval, as well as nonverbal intelligence and socioeconomic status.     

Does Posttransfer Involvement Matter for Persistence of Community College Transfer Students?

Because of increasing mobility among various college student populations, both the baccalaureate degree attainment of community college beginners and the role played by their receiving 4-year institution are growing in importance. In this study, we examined how the academic and social involvement of community college transfer students differs by the type of receiving institution, and how strongly their posttransfer involvement is associated with persistence. Results indicated that academic and social involvement were higher for students who transferred to private not-for-profit doctoral institutions, as compared to those who transferred to other types of institutions. Also, among the involvement variables, academic advising is the factor that is most positively associated with the persistence of these students. Our findings make the case for a comprehensive examination of persistence of community college transfer students, looking at both their level of involvement and the type of institution they move to.